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In a distance above the ground, my LES result is not good

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Old   January 22, 2010, 05:03
Default In a distance above the ground, my LES result is not good
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Jiang
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Dear foamers:

I am confused by my LES result. My simulation is a wind engineering problem. I use Smagorinsky model with Van Driest damping function, and Wall function the same time. Through my compration along a horizontal line behind building, my result is good near building, but smaller and smaller farer from building.

Who khows why like this ?
my simulation dt=5e-5, now the interation steps is about 60000 steps, total time is 3 second. Although the total time is not enough ,but I think my result has problem, compared to RANS result and experiment data.
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Old   January 22, 2010, 05:19
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my comparetion is along AB line. in the weak region behind building ,The LES result is good ,bu why it is not good far from building ? my positon is near ground ,if it is affected by wall function ? or by my symmetry side boundary?
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Old   January 22, 2010, 08:52
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Hi panda60,
why are you using both the VanDriest damping and wall functions ?
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